Electrical connecter plug



Dec. 7, 1937. L, H, R LE, 2,101,345

ELECTRICAL CONNECTER PLUG Filed March 20, 1936 2 Shets-Sheet 1 VENTOE.

Dec. 7, 1937. 1.. H. RILEY ELECTRICAL CONNECTER PLUG Filed March 20, 1936 2 Sheets-Sheet 2 Patented Dec. 7, 1937 UNITED STATES PATENT OFFICE 1 Claim.

My invention relates to electrical connecters for general use, including use in outlet boxes and as a connection between lamps and other electrical devices and their source of electric current.

The invention has as its principal object a connecter that is simple, sturdy and inexpensive, that is neat and inconspicuous in appearance, whose socket member is adapted for concealment by means of a. false cover plug that minimizes the danger of electrical shocks, that minimizes the risk of fraying or breaking the electric wiring and that has other important practical advantages.

The invention consists in the electrical conmeter plug and in the parts and combinations andarrangements of parts hereinafter described and claimed.

In the accompanying drawings,

Fig. l is a part elevation, part vertical sectional view, on a reduced scale, of an electrical lamp having mounted in its base an electrical connecter plug embodying my invention and also showing one oi said plugs used as a wall outlet member,

5 Fig. 2 is a part elevation, part vertical sectional view of the base portion of said lamp,

Fig. 3 is a vertical sectional view of an outlet box having mounted therein a connecter plug embodying my invention,

Fig. 4 is an elevation of the socket member of said device, looking in the direction of the arrows H,

Fig. 5 is an elevation of the plug member looking in the direction of the arrows 5-5,

5 Fig. 6 is a longitudinal sectional view through the two parts of the connecter plug device shown in Fig. 3,

Fig. 7 is a sectional view similar to Fig. 6, but

showing the two parts of the device separated 40 and ready for assembly, I

,, Fig. 8 is a sectional view on the line 8-8 of Fig. 9 is a sectional view on the line 99 in 11:. 6, 45 Fig. 10 is a sectional view on the lin Ill-i0 or Pig. 5, i

Fig. 11 is adetail view similar to Fig. 3 showing the-socket member in place and having a closure plug mounted in the end thereof, Ms 4 50 Fig. 12 is a perspective view of said plug, and

Fig. 13 is a sectional view of a modified binding post and wire terminal construction.

Fig. 1 shows electrical connecter plug devices embodying my. invention indicated generally by 55 the numeral I. one or said devices is moun e in an outlet box 2 at the base board level or a wall 3 and one in the base 4 of the tubular standard 5 of an electric lamp 6. The connecter plug device I comprises a socket member I and a plug member 8. 5 The socket member I is held in place in the base 4 oi. the lamp standard 5 by' means of a set screw 9. The'lamp wiring I0 extends from said I socket member I through the lamp standard 5 to the light bulb socket. The plug member 8 10 that cooperates therewith is mounted at the end of a suitable extension cord ll.

Fig. 3 illustrates an outlet box 2 mounted in a wall 3 at the base board level. Said outlet box 2 has a perforated cover I2 secured thereto as by 5 screws l3 and a tubular housing I! is mounted in the opening thereof and secured thereto, as by welding l5, said housing l4 projecting inwardly into the outlet box 2 and outwardly into an opening iii in the base board l1, terminating 20 flush with the outer surface of said base board;

The housing I has an annular rib i8 formed in its interior near the inner end thereof, which serves as a stop for the beveled inner edge iii of the socket member I. The plug member 81s 2 secured to the end of the extension cord ii to whose other end issecured the plug member 1 that cooperates with the socket member 8 in the lamp.

The two wires 28 of the electric wiring system 30 extend into the socket member through holes 2| in the end wall 22 thereof, and the insulation 23 is stripped from the end portions thereof, said holes being provided with. a reduced portion 24 too small in size to receive the wire 20 when covered by insulation 23, the end of the insulation resting against one face of the shoulder- 25 formed by said reduced portion 24. Against the other face of each shoulder25 is mounted the end portion 28 of. a contact strip 21, said end portions having recesses 28 therein receiving the ends of said wires 20. Screws 29 mounted in countersunk openings 30 in the sides of the socket member I are threaded through the socket membeer and through the end portions 26 of the contact strips 21 to engage the ends of the wires 20 and hold them in place. 1

r The plug member 8 has recesses 3| in the en that fits in the socket. said recesses 3! being. in line with thecontact strips 21, but of larger size.- Mounted on either side of a cross wall 32 separating said recesses 3i and projecting into said recesses are contact members 83 into which extend the plain ends of the two wires 34 01' the extension cord I I irom which the outer cover 85 and theindividual insulation 36 havebeen removed. These wires 34 are held in place in their respective contact members 3 by means of screws 31 set in countersunk openings 38 in the plug and extending through the plug and far enough through the contact members to engage the wires 34. The bores 39 through which the stripped wires 34 extend are of reduced diameter intermediate their ends to form a shoulder 40 against one side of which one of said contact members 33 abuts and the other side of which prevents the insulation 36 from extending into the contact member. The two Wire-bores 39 open into a single large bore 4| at theend of the plug, which large bore 4| is closed by an annular cap 42 fitting over the extension cord II. I I

The socket member I is provided at its outer end with a bayonet slot comprising a longitudinally extending portion 43 and an angularly offset portion 44. The socket member 1 extends slightly beyond the face of the base board I! and the plug member 8 has an annular peripheral rib 45 that overlaps the end of the socket member. Mounted in the annular channel 46 formed between said rib and the plug body are springs 41 which preferably have one end 48 embedded in the plug material.

As appears from Fig. 7, the plug 8 is arranged in line with the socket I and then rfioved endwise into the socket, the contact strips 21 entering the enlarged recesses 3| in which the contact members 33 of the plug are mounted. The plug has a pin 49 that moves along the longitudinal slot 43 in the socket until it seats against the angular portion 44 of the slot, whereupon twisting movement of the plug to move the pin into the angular locking portion 44 of the slot swings the plug into such position that the contact members 33 thereof are in engagement with 'the contact strips 21 of the socket member. lreferab'ly, both sets of contact members have curved bosses 50 which accommodate the locking movement of the plug and Y which insure firm electrical contact. The springs 41 in the end of the plug maintain the parts in locked position and" prevent accidental disengagement.

It will be understood that the foregoing detailed description of the plug and socket members mounted in the outlet box and of the wiring connections thereof is also applicable to the plug and socke members in the lamp.

As appears from Figs. 11 and 12, wall sockets which are not in usev may be closed by a plug 5| conforming in finish to the base board and having a locking pin 49 therein. The use of such' a plug prevents trapping of dirt and makes the socket quite inconspicuous.

In Fig. 13 is shown a slight modification wherein the end portion of the wire is permanently rib 62 at its end which is engaged by contact screws 29 or 31 to prevent separation of the parts.

The plug and socket members may be made of a suitable plastic, as a resin, or any other suitable composition and the contact members and the springs may be molded or cast therein.

The above described construction removes all strain from the electric wiring and separation of the two parts of the connecter can be efiected only by pressure on the plug against the force of the springs and twisting of the plug to release the bayonet lock. Thus, accidental disengagements of the parts and breaking or shorting of the electrical circuit are prevented. The electrical contact is positive and certain. The changing of cords is facilitated and a cord of the length desired at any one place may be used instead of the lamp or other device having a cord of excess length projecting therefrom. Breakage and fraying of the electric cord are prevented. The connecter is simple and inexpensive in construction, it is sturdy and durable, it is neat and inconspicuous in appearance and it is adapted for use wherever an electrical connecter is needed. For

example, it may be used in a ceiling for the separable mounting of light sockets or other fixtures. Obviously, numerous changes may be made without departing from the invention and I do not wish to be limited to the precise construction shown.

What I claim is:

An electrical connecter plug comprising a tubular socket member having an end wall, resilient electrical contact members projecting from said end wall into the socket of said member, and a .plug member fitting in said socket, said plug member having recesses in its end and electrical contact members in said recesses for external engagement with the respective contact members of the socket members, said contact members all having curved contact bosses, said socket member having a longitudinal slot at its outer end and an angular slot communicating with said longitudinal slot and said plug having a pin for cooperation with said slots and having an annular peripheral rib forming a channel between itself and the body of the plug and springs in said channel bearing against the end of the socket member for resisting separation of the parts.

LEE HUNTER RILEY. 

